<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .die {
            width: 200px;
            height: 200px;
            position: relative;
            background-color: pink;
        }
        
        .er {
            width: 50px;
            height: 50px;
            background-color: #fff;
        }
        
        .die:hover .er {
            position: absolute;
            top: 50px;
        }
    </style>
</head>

<body>
    <div class="die">
        <div class="er">
        </div>
    </div>
</body>

</html>